Exhibit 99.1
 Apache Corporation
  Estimated
 Future Reserves and Income
 Attributable to Certain
 Leasehold and Royalty Interests
 In the
 Shell Offshore Venture
  SEC Parameters
  As of
 December 31, 2009
  /s/ Jennifer A. Fitzgerald
    
    /s/ Michael F. StellJennifer A. Fitzgerald, P.E.
    
    Michael F. Stell, P.E.TBPE License No. 100572
    
    TBPE License No. 56416Senior Petroleum Engineer
    
    Managing Senior Vice President
 RYDER SCOTT COMPANY, L.P.
 [Seal]
    
    [Seal]




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SEC PARAMETERS
Apache Corporation    Shell Offshore Venture
 As of December 31, 2009ProvedDeveloped
    
    
    
    
    
    
    TotalProducing
    
    
    Non-Producing
    
    
    Undeveloped
    
    
    ProvedNet Remaining ReservesOil/Condensate  Barrels
    
    
    108,792
    
    
    
    449,269
    
    
    
    14
    
    
    
    558,075Plant Products  Barrels
    
    
    14,367
    
    
    
    80,416
    
    
    
    0
    
    
    
    94,783Gas  MMCF
    
    
    832
    
    
    
    1,866
    
    
    
    123
    
    
    
    2,821Income DataFuture Gross Revenue
    
    $
    10,247,622
    
    
    $
    37,183,453
    
    
    $
    492,491
    
    
    $
    47,923,566Deductions
    
    
    6,319,463
    
    
    
    9,117,946
    
    
    
    474,005
    
    
    
    15,911,414Future Net Income (FNI)
    
    $
    3,928,159
    
    
    $
    28,065,507
    
    
    $
    18,486
    
    
    $
    32,012,152Discounted FNI @ 10%
    
    $
    5,172,756
    
    
    $
    11,837,952
    
    
    
    -$2,579
    
    
    $
    17,008,129
  1200, 530 8TH AVENUE, S.W.
    
    CALGARY, ALBERTA T2P 3S8
    
    TEL (403) 262-2799
    
    FAX (403) 262-2790621 17TH STREET, SUITE 1550
    
    DENVER, COLORADO 80293-1501
    
    TEL (303) 623-9147
    
    FAX (303) 623-4258




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TM
    Discounted Future Net IncomeAs of December 31, 2009Discount Rate
    
    TotalPercent
    
    Proved5
    
    $22,548,80915
    
    $13,584,49620
    
    $11,342,19925
    
    $  9,790,525
  Reserves Included in This Report




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Estimates of Reserves




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Future Production Rates
   Hydrocarbon Prices
   Costs




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Standards of Independence and Professional Qualification




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Terms of Usage
  Very truly yours,RYDER SCOTT COMPANY, L.P.
TBPE Firm Registration No. F-1580/s/ Jennifer A. FitzgeraldJennifer A. Fitzgerald, P.E.TBPE License No. 100572
Senior Petroluem Engineer/s/ Michael F. StellMichael F. Stell, P.E.TBPE License No. 56416
Managing Senior Vice President




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Professional Qualifications of Primary Technical Person
  http://www.ryderscott.com/Experience/Employees.php




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PETROLEUM RESERVES DEFINITIONS
 As Adapted From:
RULE 4-10(a) of REGULATION S-X PART 210
UNITED STATES SECURITIES AND EXCHANGE COMMISSION (SEC)
 PREAMBLE




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RESERVES (SEC DEFINITIONS)
  Reserves. Reserves are estimated remaining quantities of oil and gas and related substances
anticipated to be economically producible, as of a given date, by application of development
projects to known accumulations. In addition, there must exist, or there must be a reasonable
expectation that there will exist, the legal right to produce or a revenue interest in the
production, installed means of delivering oil and gas or related substances to market, and all
permits and financing required to implement the project.
 Note to paragraph (a)(26): i.e. , absence of reservoir,
structurally low reservoir, or negative test results). Such areas may contain prospective
resources ( i.e. , potentially recoverable resources from undiscovered accumulations).
 PROVED RESERVES (SEC DEFINITIONS)
  Proved oil and gas reserves. Proved oil and gas reserves are those quantities of oil and gas,
which, by analysis of geoscience and engineering data, can be estimated with reasonable certainty
to be economically produciblefrom a given date forward, from known reservoirs, and under existing
economic conditions, operating methods, and government regulationsprior to the time at which
contracts providing the right to operate expire, unless evidence indicates that renewal is
reasonably certain, regardless of whether deterministic or probabilistic methods are used for the
estimation. The project to extract the hydrocarbons must have commenced or the operator must be
reasonably certain that it will commence the project within a reasonable time.
 (i)
    
    The area of the reservoir considered as proved includes:
 (A)
    
    The area identified by drilling and limited by fluid contacts, if any, and(B)
    
    Adjacent undrilled portions of the reservoir that can, with reasonable certainty,
be judged to be continuous with it and to contain economically producible oil or gas
on the basis of available geoscience and engineering data.
 (ii)
    
    In the absence of data on fluid contacts, proved quantities in a reservoir are limited
by the lowest known hydrocarbons (LKH) as seen in a well penetration unless geoscience,
engineering, or performance data and reliable technology establishes a lower contact with
reasonable certainty.(iii)
    
    Where direct observation from well penetrations has defined a highest known oil (HKO)
elevation and the potential exists for an associated gas cap, proved oil reserves may be
assigned in the structurally higher portions of the reservoir only if geoscience,
engineering, or performance data and reliable technology establish the higher contact with
reasonable certainty.




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(iv)
    
    Reserves which can be produced economically through application of improved recovery
techniques (including, but not limited to, fluid injection) are included in the proved
classification when:
 (A)
    
    Successful testing by a pilot project in an area of the reservoir with properties
no more favorable than in the reservoir as a whole, the operation of an installed
program in the reservoir or an analogous reservoir, or other evidence using reliable
technology establishes the reasonable certainty of the engineering analysis on which
the project or program was based; and(B)
    
    The project has been approved for development by all necessary parties and
entities, including governmental entities.
 (v)
    
    Existing economic conditions include prices and costs at which economic producibility
from a reservoir is to be determined. The price shall be the average price during the
12-month period prior to the ending date of the period covered by the report, determined as
an unweighted arithmetic average of the first-day-of-the-month price for each month within
such period, unless prices are defined by contractual arrangements, excluding escalations
based upon future conditions.




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RESERVES STATUS DEFINITIONS AND GUIDELINES
 As Adapted From:
RULE 4-10(a) of REGULATION S-X PART 210
UNITED STATES SECURITIES AND EXCHANGE COMMISSION (SEC)
 and
 PETROLEUM RESOURCES MANAGEMENT SYSTEM (SPE-PRMS)
Sponsored and Approved by:
SOCIETY OF PETROLEUM ENGINEERS (SPE),
WORLD PETROLEUM COUNCIL (WPC)
AMERICAN ASSOCIATION OF PETROLEUM GEOLOGISTS (AAPG)
SOCIETY OF PETROLEUM EVALUATION ENGINEERS (SPEE)
  DEVELOPED RESERVES (SEC DEFINITIONS)
  Developed oil and gas reserves are reserves of any category that can be expected to be
recovered:
 (i)
    
    Through existing wells with existing equipment and operating methods or in which
the cost of the required equipment is relatively minor compared to the cost of a new
well; and(ii)
    
    Through installed extraction equipment and infrastructure operational at the
time of the reserves estimate if the extraction is by means not involving a well.
 Developed Producing (SPE-PRMS Definitions)
  Developed Producing ReservesDeveloped Producing Reserves are expected to be recovered from completion intervals that are
open and producing at the time of the estimate.Improved recovery reserves are considered producing only after the improved recovery project
is in operation.Developed Non-ProducingDeveloped Non-Producing Reserves include shut-in and behind-pipe reserves.




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Shut-InShut-in Reserves are expected to be recovered from:
 (1)
    
    completion intervals which are open at the time of the estimate but which
have not yet started producing;(2)
    
    wells which were shut-in for market conditions or pipeline connections;
or(3)
    
    wells not capable of production for mechanical reasons.
 Behind-PipeBehind-pipe Reserves are expected to be recovered from zones in existing wells which will
require additional completion work or future re-completion prior to start of production.In all cases, production can be initiated or restored with relatively low expenditure
compared to the cost of drilling a new well.
 UNDEVELOPED RESERVES (SEC DEFINITIONS)
  Undeveloped oil and gas reserves are reserves of any category that are expected to be
recovered from new wells on undrilled acreage, or from existing wells where a relatively
major expenditure is required for recompletion.
 (i)
    
    Reserves on undrilled acreage shall be limited to those directly
offsetting development spacing areas that are reasonably certain of production
when drilled, unless evidence using reliable technology exists that establishes
reasonable certainty of economic producibility at greater distances.(ii)
    
    Undrilled locations can be classified as having undeveloped reserves only if a
development plan has been adopted indicating that they are scheduled to be drilled
within five years, unless the specific circumstances, justify a longer time.(iii)
    
    Under no circumstances shall estimates for undeveloped reserves be attributable
to any acreage for which an application of fluid injection or other improved recovery
technique is contemplated, unless such techniques have been proved effective by
actual projects in the same reservoir or an analogous reservoir, as defined in
paragraph (a)(2) of this section, or by other evidence using reliable technology
establishing reasonable certainty.